Process in direct-action driers



I. M. JUSTICE.

PROCESS IN DIRECT ACTION DRIERS.

APPLICATION FILED MAY 3. 1919.

1,393,788. Patented Oct. 18, 19 21.

4 SHEETSSHEET l.

I. M. JUSTICE.

PROCESS IN DIRECT ACTION DRIERS.

APPLICATTON FILED MAY 3, I919.

1,398,788, Patented Oct. 18, 1921.

4 SHE TSS HEET 2- Jul entw- I, M. JUSTICE.

PROCESS IN DIRECT ACTION BRIE RS.

APPLICATION FILED MAY 3, 1919.

1,393,788. Patented Oct 18, 1921.

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@MAVQ I. M. JUSTICE.

PROCESS IN DIRECT ACTION DRIERS.

APPLICATION FILED MAY 31 I919.

1,393,788. Patented 0@1;.18,1921.

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UNITED STATES PATENT OFFICE.

ITHAMAR M. JUSTICE, OF DAYTON, OHIO, ASSIG-NOR TO THE MANUFACT EQUIPMENT COMPANY, OF DAYTON, OHIO, A CORPORATION .OF OHIO,

PROCESS IN DIRECT-ACTION DRIERS.

Specification of Letters Patent.

Patented Oct. 18, 1921.

Application filed May 3, 1919. Serial No. 294,499.

To all whom it may concern:

Be it known that I, ITHAMAR M. JUSTICE,

a citzen of the United States, residing at Dayton, in the county of Montgomery and State of Ohio, have invented certaln new and useful Improvements in Processes 1n Direct-Action Driers, of which the following is a specification, reference being had therein to the accompanying draw ng.

This invention consists of an improved process of manufacturing relating to direct action driers for ceramic products and has for its particular object to provide a process at the receiving end of the tunnels and there- 7 fore movable in the direction the product is moved through the tunnels. 7

Under the preferred arrangement the furnaces are located at the end of the driers opposite the receiving end, the heat being conducted through underground heating tunnels extending parallel with the drying tunnels substantially the full length of the latter, and then conducted upwardly through suitable fines to heating channels communieating with a stack located, preferably, approximately at the central P01131011 of the structure. By such an arrangement the maximum amount of heat radiation is obtained in the drying tunnels from below and above, and the air passing therethrough is maintained at even temperatures which gradually increase from warm or comparatively low temperatures at the receiving end of the drying tunnels to hot or relatively high temperature at the delivering end.

With the gradual increase in temperature of the air as it passes through the drying tunnels, its moisture carrying capacitly is increased accordingly but in greatly increased proportion.

It is a well known physical law that at 42 F. one pound of air will carry .089 oz. of moisture; at 82, .38 oz.; at 132, 1.88

oz. and at 182, 11.4 oz. Thus it will be ob-" served that the increase in moisture carrying properties of the air is very great with a relatively small increase in temperature.

In the application of this natural law of evaporation, it iswell known that if the air 1n a process of drying conducted on this princlple leaves the tunnel at 162 F., the welght necessary to carry one pound ,of water is only 3.1 pounds or 48% cubic feet, as compared with 50% pounds or "89 cubic feet required in a drier operated on the inverse system, i. 6., in which the air moves opposite the direction the product is moved through the tunnels, and working between 82 and 170.

Therefore, by means of my improved process the drying operation is greatly facllltated, is much more uniform, and less liable to cause waste in the finished product by cracking, as the moisture carrying capaclty of the air increases so rapidly with the gradual increase in temperature that there is no condensation on the ware.

Most clays, including the delicate or tender grades, may be dried under the improved process in the comparatively short time of thirty hours, thus effecting a large saving in fuel as well as improving the quality of the product and minimizing the usual waste resulting from cracking which are inevitable under constructions and processes where the inverse system is practised.

Under my improved process during the greater part of the drying operation the air is so charged with moisture as to be nearly saturated; the increase in temperature being gradual and uniform, strong air currents and excessive surface drying are avoided, and delicate clays, which inevitably crack under the inverse system of drying, may be successfully treated by the new process with a minimum of waste and otherwise highly satisfactory results.

An important step in the new process of direct action drying is provided for by locating the stack intermediate the receiving; and delivering ends of the drying tunnels. By such an arrangement the hot'moisture laden air as it rises from the hot end of the tunnels is carried, as shown in the present arrangement, through channels leading to the stack and extending parallel with the drying tunnels, thus acting to heat the-ceilings of the tunnels and aiding thereby to maintain the uniformity of temperature within the tunnels which is so essential to obtaining the best results with the product.

While the principle of direct action drying .by introducing the air at atmospheric temperature at the receiving end of the drying tunnels and causing it to pass therethrough in the same direction as the product, is not broadly new per se', the particular steps of the present process of treatment in various important particulars are new and tend to bring about results which, considered separately and as a whole, are a marked improvement over the earlier practice with respect to the shorter time required for the drying operation, the reduction in fuel requirements, and the reduction in waste or loss in the finished product.

In the accompanying drawings a construction of an improved type is illustrated in one form in which the present invention may be effectually applied. Driers of the type shown are usually of large construction consisting of a plurality of drier units, all of which are essentially alike in construction and general arrangement.

As here shown Figure 1 illustrates a side elevation taken in longitudinal section, and showing the arrangement of the furnaces, the fuel and drying tunnels and the channels of air passages leading therefrom to the common stack.

Fi 2 isa cross sectional view taken on the hue 2-2 of Fig. 1, and looking in the direction of the arrows.

Fig. 3 is a cross section view taken on the line 3-3 of Fig. 1, having the upper portion of the stack broken away.

Fig. 4 is a plan. view in cross section of the receivin end of the dryer taken on the line 44 of ig. 3.

Fig. 5 is an enlarged detailed plan view taken on the line 5-5 of Fig. 1; and

Fig. 6 is an enlarged detailed View in elevation of the upper portion of one of the heat flues. j

The process as practised in a construction of the character shown consists in heating the furnaces 1, in any suitable manner as by coal or gas fuel, and in conducting the heat from the furnaces through the tunnels 2 into cross tunnels or chambers 3, and thence up wardly through flues 4 into the heating or dry alr channels 5, which extend parallel with the drying tunnels 6 and lead direct into the stack 7. The metal arch 8 and ceilings 9 of the drying tunnels are thus heated by radiation, the temperature within the driers increasing gradually from the end of the tunnels farthest removed from the furnaces, which is known as the cold end of the driers, to the opposite end which is known as the hot end. Partition walls 10, 11, 12 and 13 are interposed respectively between the different units of the fuel and drier tunnels and the draft channels leading to the stack.

A further step in the process consists in introducing the air, which absorbs and carries off the moisture from the product, at atmospheric temperature to the drying tunnels at their cold ends, and causing the air to pass through the driers in the same direction as the productis moved, the air being gradually increased in temperature by the heat radiated from the floor, side Walls and ceiling of the tunnels and absorbing relatively greater quantities of moisture until the highest temperature required in the process is attained at the hot end of the tunnels; the saturated air then passing upward through suitable draft apertures in the ceilings of the tunnels is conducted through channels 14 extending parallel with the drying tunnels and leading direct into the stack 7 A partition wall 15 serves to divide the dry air channels 5 and moist air channels 14 to prevent intermingling of the two atmospheres until they pass upwardly into the stack. This arrangement is for the purpose of maintaining uniformity of temperatures, to prevent condensation of the moist atmosphere, and to improve the draft.

By means of air pits 16 and air passages 17 leading therefrom into the cold'ends of the drier tunnels the supply of fresh air to the tunnels at atmospheric temperature is constant, the quantity being regulated by the size of the opening 18 in the wall 19. It is an important feature of the process to supply the quantity of air required to obtain the best results in drying. This is determined by experience and should be regulated to suit the character of clay used in the product. It is a further feature of the process to maintain temperatures, by properly balanced heating and draft regulations, that will cause the air to be near saturation at all points in its passage through the drying tunnels. Thus the drying process is maintained relatively uniform to the variations in temperature and the law of increase in its moisture carrying qualities, and the process proceeds and arrives at completion in the shortest time and with the minimum of fuel consumption.

In the application of the process the drying tunnels are provided with the usual tracks 20, and any suitable trucks or cars may be used for supporting the ware and carrying the same through the drying process, the ends of the tunnels being closed in the usual manner by doors 21.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent, is

1. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at' one end with a fur- III nace, said heating tunnel being provided at the end opposite the furnace with a flue ex tending upwardly to heating channels parallel with said drying and heating tun-i nels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature into the end of the drying tunnel opposite the furnace end of the heating tunnel, and conducting it therethrough and upwardly near the furnace end thereof into and through the air channel extending to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

2. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furance end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating cl .nnels to the stack; in introducing air at atmospheric temperature into the end of the drying tunnel opposite the furnace end of the heating tunnel, and conducting it therethrough and upwardly near the farther end thereof into and through an air channel extending over the drying tunnel to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

3. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a fine extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature into the end of the drying tunnel opposite the furnace end of the heating tunnel, and conducting it therethrough and upwardly near the furnace end thereof into and through the air channel extending over and parallel with the drying tunnel to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

4;. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels .to the stack; in introducing air constantly at atmospheric temperature into the end of the drying tunnel opposite the furnace end of the heating tunnel, and conducting it therethrough and upwardly near the furnace end thereof into and through the air channel extending over the drying channel to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

5. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature in regulated quantities into the end of the drying tunnel opposite the furnace end of the heating tunnel, and conducting it therethrough and upwardly near the .furnace end thereof into and through the air channel extending over the drying tunnel to the stack, in introduc-' ing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

6. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connected at one end with'a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air constantly at atmospheric temperature in regulated quantities into the end of the drying tunnel opposite the furnace end of the heatin tunnel, and conduct-in it therethrough and upwardly near the furnace end thereof into and throu h the air channel extending over and parallel with the drying tunnel to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

7. The herein described process of heat treating materials in a drying tunnel having beneath and parallel there-with a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature in regulated quantities into the end of the dryin tunnel opposite the furnace end of the heating tunnel, in causing the same to be gradually increased in temperature by radiation of heat as it passes therethrough and in conducting it upwardly near the furnace end thereof into and through the air channel extending over and parallel with the drying tunnel to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

8. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening-into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature in regulated quantities into the end of the drying tunnel opposite the furnace end of the heating tunnel, in causing the same to be raduall increased in temperature by radiation of said heat and to be maintained approximately at the point of saturation as it passes through the drying tunnel upwardly near the furnace end thereof into and through the air channel extending to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

9. The herein described process of heat treating materials in a drying tunnel having beneath and parallel therewith a heating tunnel connecting at one end with a furnace, said heating tunnel being provided at the end opposite the furnace with a flue. extending upwardly to heating channels parallel with said drying and heating tunnels and leading to a stack intermediate the ends of the drying tunnel and there being also at the furnace end of the drying tunnel an outlet for the air therein opening into a channel leading to the stack; the process consisting of passing a heating medium through the heating tunnel thence upwardly through the end flue to and along the heating channels to the stack; in introducing air at atmospheric temperature in regulated quantities into the end of the drying tunnel opposite the furnace end of the heating tunnel, in causing the same to be gradually increased in temperature by radiation of said heat and to be maintained slightly below the point of saturation as it passes through the drying tunnel upwardly near the furnace end thereof into and through the air channel extending to the stack, in introducing into the drying tunnel the material to be treated and in advancing it therealong in the direction of the air current.

In testimony whereof I aflix my signature.

ITHAMAR M. JUSTICE. 

